脊椎动物的线粒体DNA(mtDNA)是一段长度约为15-22Kb的环形片段,具有相对的保守性。D-loop区是线粒体基因组中的非编码区域的一部分,具有控制和调节的功能。本文采用LA-PCR和生物信息学的方法,研究了大蹼铃蟾的线粒体基因组D-loop区序列,...脊椎动物的线粒体DNA(mtDNA)是一段长度约为15-22Kb的环形片段,具有相对的保守性。D-loop区是线粒体基因组中的非编码区域的一部分,具有控制和调节的功能。本文采用LA-PCR和生物信息学的方法,研究了大蹼铃蟾的线粒体基因组D-loop区序列,其D-loop区具有三个保守序列(CSB-1,CSB-2 and CSB-3),在5`和3`端还有独特的串联重复序列。通过分析总结其串联重复序列的特征和规律,有助于研究蛙科动物线粒体基因组进化机制。展开更多
Four parameters of chemical bond havebeen used to span a feature space to classifyquasicrystal-forming Al-alloys from thatalloys without quasicrystal formationwith good result. Since the first quasicrystal-formingsyst...Four parameters of chemical bond havebeen used to span a feature space to classifyquasicrystal-forming Al-alloys from thatalloys without quasicrystal formationwith good result. Since the first quasicrystal-formingsystem, Al-Mn system, discovered by She-chtman in 1984[1], a series of quasicrystal-forming binary alloy systems have beenfound. Most of these systems are Al-contain-ing systems. Bancel has indicated thatthere are three factors affecting theformability of quasicrystals [2]: (1) ele-ctrochemical factor (this factor can be展开更多
In this paper, we give further discussions about our new method of bond spherical har-monics with equal number of near neighborst, and study the molten salt LiCl and itsquenching process by means of molecular dynamics...In this paper, we give further discussions about our new method of bond spherical har-monics with equal number of near neighborst, and study the molten salt LiCl and itsquenching process by means of molecular dynamics simulation. The bond order parametersQ_l at different temperatures are calculated by averaging the Q_l values of the computer-generated instantaneous configurations at each time-step. By consulting the Q_l histogramsof the linear combination models with a parameter of square deviation σ we find that theQ_l Listograms from the simulation and those from the combination model with 90% localtetrahedron structure are very similar. The results indicate that the local bond orientationin the quenched LiCl system tends strongly to be tetrahedron. The local bond-orientationalorders in the quenching process can be described by the same linear combination, but thesquare deviation varies with the temperature. The square deviation decreases with thelowering of temperature and drops rapidly when the glass transition takes place. The bondangle distributions are also calculated and it is found that the angles gather about 109°(the=bond angle of tetrahedron) and the peaks of the distributions Lave a wider spread as temper-iature increases, in accordance with the results from Q_l.展开更多
文摘脊椎动物的线粒体DNA(mtDNA)是一段长度约为15-22Kb的环形片段,具有相对的保守性。D-loop区是线粒体基因组中的非编码区域的一部分,具有控制和调节的功能。本文采用LA-PCR和生物信息学的方法,研究了大蹼铃蟾的线粒体基因组D-loop区序列,其D-loop区具有三个保守序列(CSB-1,CSB-2 and CSB-3),在5`和3`端还有独特的串联重复序列。通过分析总结其串联重复序列的特征和规律,有助于研究蛙科动物线粒体基因组进化机制。
基金supported by the National Key Basic Research Program of China(973)(2013CB921802)Fundamental Research Funds for the Central Universities,China,State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources,China(KSL-CUSAb-2012-03)~~
文摘Four parameters of chemical bond havebeen used to span a feature space to classifyquasicrystal-forming Al-alloys from thatalloys without quasicrystal formationwith good result. Since the first quasicrystal-formingsystem, Al-Mn system, discovered by She-chtman in 1984[1], a series of quasicrystal-forming binary alloy systems have beenfound. Most of these systems are Al-contain-ing systems. Bancel has indicated thatthere are three factors affecting theformability of quasicrystals [2]: (1) ele-ctrochemical factor (this factor can be
基金Project supported by the National Natural Science Foundation of China.
文摘In this paper, we give further discussions about our new method of bond spherical har-monics with equal number of near neighborst, and study the molten salt LiCl and itsquenching process by means of molecular dynamics simulation. The bond order parametersQ_l at different temperatures are calculated by averaging the Q_l values of the computer-generated instantaneous configurations at each time-step. By consulting the Q_l histogramsof the linear combination models with a parameter of square deviation σ we find that theQ_l Listograms from the simulation and those from the combination model with 90% localtetrahedron structure are very similar. The results indicate that the local bond orientationin the quenched LiCl system tends strongly to be tetrahedron. The local bond-orientationalorders in the quenching process can be described by the same linear combination, but thesquare deviation varies with the temperature. The square deviation decreases with thelowering of temperature and drops rapidly when the glass transition takes place. The bondangle distributions are also calculated and it is found that the angles gather about 109°(the=bond angle of tetrahedron) and the peaks of the distributions Lave a wider spread as temper-iature increases, in accordance with the results from Q_l.
